Last updated: July 2, 2025
In Clayton, understanding the UV Index is crucial for protecting your skin from harmful UV radiation, especially during the peak summer months when risk levels can soar. The UV Index provides a reliable measure of sunburn potential, helping residents and visitors alike make informed decisions about outdoor activities. With Clayton's climate presenting a Cfa classification, characterized by humid summers, the risk of intense UV exposure is notably higher during midday hours—reaching as high as 10. By staying aware of daily UV levels, you can take proactive steps to safeguard your skin health and avoid the long-term effects of sun exposure.
The UV Index starts off gentle in the early hours, peaking at 1 around 07:00 and 08:00. As the sun ascends, it gradually climbs to reach 2 by 09:00 and then surges to 4 by 10:00. A significant spike occurs around 11:00, peaking at 6, before reaching its zenith of 10 from 13:00 to 14:00—a crucial time for sun protection. As the afternoon wanes, the index begins to decline, tapering down to 7 at 16:00, then to 5 by 17:00. As the sun sets, it drops to 3 at 18:00, and finally sinks back to a safe 1 by 19:00, reminding us to be cautious in the midday sun while enjoying the warm daylight.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 4 | moderate | 30 min |
| 11:00 | 6 | high | 25 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 9 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 1 | low | 45 min |
As the seasons shift, the UV Index reveals a significant increase in ultraviolet radiation, particularly from March to September, indicating a heightened risk of sunburn and skin damage. The high-risk months are clearly defined from April to August, with the peak reaching a UV Index of 11 in June. During these times, the exposure category escalates to very high or extreme, resulting in a burn time as short as 10 minutes. Visitors and residents are strongly advised to take precautionary measures by wearing protective clothing, applying sunscreen, and seeking shade, especially during midday hours when the sun's intensity is at its peak. As the UV Index decreases in the fall and winter months, maintaining awareness and protection remains essential to ensure skin health year-round.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chicago UVI | 3 | 4 | 6 | 8 | 9 | 10 | 10 | 9 | 8 | 6 | 4 | 2 |
| Brooklyn UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| New York City UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| Clayton | 3 | 5 | 7 | 9 | 10 | 11 | 10 | 9 | 8 | 6 | 4 | 3 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |